International Building Code
Illinois leaves the IBC to cities and counties
Illinois leaves the IBC to cities and counties. Adopted by General Assembly (statute); municipalities and counties adopt local codes. The legal citation is 20 ILCS 3105/10.18; 20 ILCS 3105/10.09-1.
Record of adoption
Edition in force
Local adoption
Partial
- Legal citation
- 20 ILCS 3105/10.18; 20 ILCS 3105/10.09-1
- Adopted by
- General Assembly (statute); municipalities and counties adopt local codes
- Second reading
- Applies
- Local option
Cities and counties adopt their own building codes; there is no statewide building code. From Jan 1, 2025, local codes must regulate structural design at least as strictly as the least restrictive IBC edition first published in the current or preceding 9 years; no single edition is named in statute, so edition is null.
Exceptions
- Chicago enforces the 2019 Chicago Building Code (Title 14B)
- Floor covers structural design only; zoning ordinances excluded
How Illinois adopts the IBC
The statute itself defines the baseline as a rolling ten-year window of ICC editions, so no agency rule is needed to move it. Local governments adopt their own codes and must report the model code and edition to CDB at least 30 days before the effective date. P.A. 103-510 created the requirement.
Cycle. Rolling baseline set by statute; local adoption irregular
Laws, rulings, and other actions
- LegislationP.A. 103-0510 (SB 2368, 103rd General Assembly)
Requires municipal and county building codes to meet a rolling IBC/IEBC/IRC structural baseline from Jan 1, 2025, and sets IBC/NEC defaults for jurisdictions without a building code.
Enacted 2023, effective Jan 1, 2024; local structural-design floor begins Jan 1, 2025
ilga.gov (opens in a new tab)
How it was checked
Partial
Researched in the state’s own record. The seal stays broken until the passage is on file word for word.
Read twice: a second, blind reading of the state’s record agreed with the first on .
The state’s record was last read on , from four source pages.
Evidence 4 sources
Sources for the record itself come first, the state’s own records ahead of others. A label marks a source about something else, such as an exception. A source marked secondary is not the state’s own record.
20 ILCS 3105/10.18 Identification of local building codesIllinois General Assemblyilga.gov (opens in a new tab)StatuteRetrieved Building Codes and RegulationsIllinois Capital Development Boardcdb.illinois.gov (opens in a new tab)Agency pageRetrieved About an exception
“incorporates provisions of the 2017 National Electrical Code”
“2019 Chicago Building Code (Title 14B)”
“Effective November 1, 2022”
Chicago Building Code OnlineCity of Chicago Department of Buildingschicago.gov (opens in a new tab)Agency pageRetrieved About the note
“the International Building Code, | | | including Appendix G and excluding Chapters 11, 13, and 29”
“current edition or most recent preceding edition”
20 ILCS 3105/10.09-1 Certification of inspectionIllinois General Assemblyilga.gov (opens in a new tab)StatuteRetrieved
Tracker cross-checks
Code adoption trackers are a cross-check. They are not Illinois’s own record.
ICC’s code adoption mapCross-checkAgrees with the record
X (one or more state or local agencies adopted an edition that is not the standard for all buildings); chart as of 2026-04